We adopt the sending-or-not-sending (SNS) protocol [1]} with actively odd parity pairing (AOPP) [2]}, [3]} method for post data processing in field experiment of TF-QKD. In this protocol, Alice and Bob use three weak coherent state (WCS) sources in the \(X\)  basis, \(\mu _1\) , \(\mu _2\) , 0, which are used for the decoy-state analysis. And in the \(Z\)  basis, Alice and Bob randomly decide sending the WCS pulses \(\mu _z\)  or not sending, where those pulses are used to extract the final keys. To improve the key rate, we take the odd parity error rejection method through AOPP in the post data processing, which can efficiently deduce the bit-error rate of the raw keys and thus largely improves the key rate. We use the zig-zag approach proposed in Ref. [4]} to analyses the finite key effects of AOPP, which assure the high performance of SNS-TF-QKD protocol with AOPP in the finite key size.
